<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>display</title>
    <style>
        .container{
            width: 200px;
            height: 200px;
            background: yellow;
        }
        span{
            background: yellow;
            display: block;
        }
    </style>
</head>
<body>
<div class="container">

</div>
<br><br>
<span>这是一个span标签</span>
<span>这是一个span标签</span>
<span>这是一个span标签</span>
</body>
</html>